feat(simulation): add NPC name masking with role labels and color index

Server-side infrastructure for information asymmetry in dialogue.
NPCs display role labels (Worker, Supervisor, Patron) instead of
real names until the player explicitly learns them via KG lookup.
NpcColorIndex (stable_id % 8) persists across name reveal.

ConversationEvent and DialogueResponseEvent carry display names +
color indices on the wire with serde(default) for compat.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/simulation/input.rs

@@ -2,7 +2,7 @@
 // Timestamped player input events for deterministic simulation (D-010 principle 4)
 // PlayerInput: semantic actions (MoveNorth, Interact, UsePerceptionMode, ToggleStance)
 
-use crate::bridge::types::{PlayerAction, PlayerInput};
+use crate::bridge::types::{FacingDirection, PlayerAction, PlayerInput};
 use crate::knowledge::{EntityRegistry, StableId};
 use crate::perception::vision_cone::{facing_from_delta, Facing};
 use crate::simulation::inventory::{
@@ -237,6 +237,27 @@ pub fn process_player_input(
                     tracing::debug!("WalkAway: marker set on player");
                 }
             }
+            PlayerAction::SetFacing { ref facing } => {
+                let dir = match facing.as_str() {
+                    "North" => Some(FacingDirection::North),
+                    "Northeast" => Some(FacingDirection::Northeast),
+                    "East" => Some(FacingDirection::East),
+                    "Southeast" => Some(FacingDirection::Southeast),
+                    "South" => Some(FacingDirection::South),
+                    "Southwest" => Some(FacingDirection::Southwest),
+                    "West" => Some(FacingDirection::West),
+                    "Northwest" => Some(FacingDirection::Northwest),
+                    _ => {
+                        tracing::warn!("SetFacing: unknown direction {:?}", facing);
+                        None
+                    }
+                };
+                if let Some(dir) = dir {
+                    if let Ok((entity, _, _, _)) = player_query.single_mut() {
+                        commands.entity(entity).insert(Facing(dir));
+                    }
+                }
+            }
             PlayerAction::TeleportToHub => {
                 handle_teleport_to_hub(&mut player_query, &mut commands);
             }